The present invention relates to storage backup techniques, and more particularly, to a technique for backing up storage in a remote place.
Since contents of disk storage may be lost by an unexpected accident, data backup is made in most computer systems. Further, data backup tape and other media are kept in a remote site so that they will not be lost together with the original copies in case of a fire, earthquake or the like. Accordingly, a SAN (storage area network)—used backup method is disclosed in Japanese Patent Laid-open No. 2002-7304. Also in Japanese Patent Laid-open No. 2000-82008, a data sharing-based backup method is disclosed.
Large-scale earthquakes, synchronized attacks by viruses, etc. prove a further growing threat to computer systems and their data, which is making it mandatory to keep two or three copies of each data as well as backing up them in a remote site. Backup is therefore becoming a swelling burden in terms of storage capacity, cost and overhead.